Jennifer M. Garrison
                                                                                            University of Iowa                                     Research Interests
Geology Slab melting paper                                  Department of Geoscience
Comment and Reply                                                            Iowa City, IA 52242                                 Current Research
                                                                                           Phone (319)335-1818
                                                                                           Fax (319) 335-1821                                  Teaching Interests
                                                                                    jennifer-m-garrison@iowa.edu
                                                                       Curriculum Vitae  (PDF version)

Present Position

MARGINS Post-doctoral Fellow: Time-scales and mechanisms of differentiation of mafic parents 
to rhyodacite in Central America.   Abstract on NSF website.  Start date 1 September, 2004, in progress.  
Project Director, Dr. Mark Reagan

Academic Degrees

1995    B.S., Environmental Geology, Colorado State University, Fort Collins, Colorado

1997    M.S., Geology, New Mexico State University, Las Cruces, New Mexico
            Implications of allochthogenic carbonate and meta-igneous blocks
            from Papalote evaporite diapir, La Popa basin, Nuevo Leon, Mexico.
           Advisor: Dr. Nancy J. McMillan

2004   Ph.D., Geology, University of California, Los Angeles;
            Magmatic processes at Cotopaxi volcano, Ecuador: Geochemical and petrological
            constraints, and inferences for continental arc volcanoes
            Advisors: Dr. Jon P. Davidson and Dr. Mary Reid

Research Interests

Igneous petrology; volcanology, physical and geochemical evolution of magma systems;
application of 238U-series disequilibrium to igneous petrology and carbonate/marine geology.
Tectonic-magmatic associations in extensional settings.

Research Experience

9/03-6/04    UCLA Dissertation research
9/02-6/03    UC Presidential Dissertation Year Fellow, Dissertation research – ion
                     microprobe analyses of zircon - directed by Mary Reid
4/02-6/02    U-Th analyses at Univ.of Bristol, UK, oxygen isotope analyses at Univ. College
                     of London, Royal Holloway - directed by Dave Lowry
9/01-12/01  U-series isotope analyses at the Univ. of Bristol, UK, directed by Simon            
                     Turner and Georg Zellmer
7/00              Field work, Cotopaxi volcano, Ecuador
4/99-6/99     Dissertation research – isotopic and electron microprobe analyses
6/99-8/99     Field work at Cotopaxi volcano, assisted staff at the Instituto Geofisico,           
                      Quito with equipment installation at Pinchincha, Antisana and Tungurahua        
                      volcanoes
1/99              Preliminary field research at Cotopaxi Volcano, Ecuador
1/96, 5/96    Field work, Papalote evaporate diaper, La Popa sedimentary basin,            
                      Nuevo Leon, Mexico


Teaching Experience

6/04-8/04        Part time faculty at Santa Monica College, Physical Geology
1/04-5/04        Part time faculty at the University of Judaism, Los Angeles
                         Course:  Geologic Hazards and Natural Resources of Southern California.
1/04-5/04        Part time faculty at California State Univ., Long Beach, General Geology.
6/01-8/01        Teaching Assistant with Dr. Gary Axen, UCLA Geology Summer Field Camp
9/00-6/01        Teaching Fellow with Dr. Mike Vendrasco, UCLA for the undergraduate            
                         Cluster Course “Evolution of the Cosmos and Life”.  Also taught a seminar        
                         entitled “Geologic Hazards and Natural Resources of Southern California”.
9/98- 6/00        Teaching Assistant with Dr. Jon Davidson, UCLA, courses in Igneous            
                          Petrology (1 quarter) and Physical Geology (4 quarters)        
1/98-7/98        Instructor, Department of Geology and Geological Engineering,                
                         University of Mississippi, Oxford, MS. Taught Introductory Geology and            
                         Physical Geography courses. 
8/95-6/97        Teaching Assistant, New Mexico State University, Las Cruces, NM.             
                         Taught laboratory sections of Physical Geology, Historical Geology,            
                         Igneous Petrology and Mineralogy/Crystallography.

Analytical Experience

VG Sector 54 thermal ionization mass spectrometer (Rb-Sr, Sm-Nd, Pb, Ra isotopic
analyses of whole rocks) with WARP energy filter and ion counting
ThermoFinnigan NEPTUNE multicollector ICP-MS (U-Th isotopic analyses of
whole rocks and mineral separates)
Cameca ims 1270 ion microprobe (U-Th and U-Pb dating of zircon)
Cameca Camebax and JEOL Superprobe electron microprobes
LEO 1470 scanning electron microscope
OPTIMA mass spectrometer using laser fluorination technique (oxygen isotopes)
Clean lab separation of elements for isotopic analysis

Funding

2004    MARGINS Postdoctoral Fellowship (with Dr. Mark Reagan)    $120,000                    
1999    National Science Foundation Research Grant                                       
            (with Dr. Jon P. Davidson)                                                             $180,000          
1999    Latin American Studies Research Grant                                    $ 1,700
1998    Geological Society of America Research Grant                        $ 2,000
1995    Geological Society of America Research Grant                        $ 2,000
1995    American Association of Petroleum Geologists Award            $ 1,800

Honors

UCLA
    2002-2003     UC Presidential Dissertation Year Fellowship   
 
New Mexico State University
    1997    Charles C. Gunn Memorial Scholarship                                   $ 500 
    1996    Council of Higher Education Research Grant                          $ 500 
    1996    Beverly Welnitz Award for Academic Excellence                    $ 500 
 
Colorado State University
    1995    Honor Senior in Geology
    1995    Rocky Mtn. Assoc. of Geologists Outstanding Student Award
    1994    Faculty and Staff Scholarship                                                     $ 200
    1994    David Harris Memorial Scholarship                                           $ 350
    1993    Chevron Scholarship                                                                    $ 2,000
 

Publications

Garrison, J.M. and Davidson, J.P., 2004, Reply to Comment: Dubious case for slab melting in the
Northern volcanic zone of the Andes: Geology online forum.

Garrison, J.M. and Davidson, J.P., 2003, Dubious case for slab melting in the Northern volcanic
zone of the Andes: Geology v. 310 no. 6, p. 565-568.

Garrison, Jennifer M. and McMillan, Nancy J., 1999, Evidence for Jurassic continental rift magmatism
in NE Mexico:  Allochthonous meta-igneous blocks in El Papalote evaporite diapir, La Popa Basin,
Nuevo Leon, Mexico: Geological Society of America Special Paper 340, p. 319 – 331.

Garrison Jennifer M., 1998, Implications of allochthogenic carbonate and meta-igneous blocks
from El Papalote evaporite diapir, La Popa basin, Nuevo Leon, Mexico:  Masters Thesis, New
Mexico State University, 160 p.

Garrison, J.M., and McMillan, N.J., 1997, Origin and implications of allochthogenic blocks
in El Paplote evaporite diapir, La Popa basin, Mexico.  AAPG Field Trip Guide Book #10,
Structure, Stratigraphy and Paleontology of Late Cretaceous-Early Tertiary Parras-La Popa
Foreland Basin near Monterrey, Northeast Mexico, p. 116-125.

Abstracts

Garrison, J.M., Davidson, J.P., Turner, S.P., Mothes, P. and Hall, M., 2002, 238U-232Th-226Ra 
disequilibria at Cotopaxi volcano, NVZ, Ecuador: EOS Transactions, American Geophysical Union.

Garrison, J.M., Davidson, J.P., Mothes, P. and Hall, M., 2000. An alternative to slab melting in
 the Northern Volcanic Zone of the Andes: EOS Transactions, American Geophysical Union.

Lawton, T.F., Garrison, J.M., and McMillan, N.J., 1997, Late Jurassic transtensional borderland
on the southwestern margin of North America: GSA Abstracts with Programs, v. 29, no. 7.

In Press

Davidson, J. P., Hora, J.,  Garrison, J.M., and Dungan, M. 2004, Crustal forensics in arc magmas,
Journal of Volcanology and Geothermal Research.

Garrison, J.M., Davidson, J.P., Reid, M.R. and Turner, S. P., Multi-level crustal     assimilation at
Cotopaxi Volcano, Ecuador; U-series investigations


Current Research

     I am currently involved in research project that is focused on rhyolites and rhyodacites from young volcanic complexes (less than 20,000 years old) in El Salvador and Nicaragua.  The goal is to to determine how  voluminous magmas capable of caldera-producing eruptions are generated, and over what time-scales they evolve. Ilopango, Apoyo, and Apoyeque calderas were chosen for this study based on age and range of volumes to provide a better understanding of emplacement times for subduction zone-related magmas in the area. These sites are within the Central America focus site of the NSF-funded MARGINS Seismogenic Zone and Subduction Factory initiatives, whose purposes are to answer questions about the growth and evolution of the lithosphere and provide information to evaluate and perhaps mitigate hazards associated with subduction zone volcanism. Whole rock samples and mineral separates from these volcanic complexes will be analyzed for U, Th, and Ra nuclide abundances, Sr-Nd-Pb-Hf and O isotopes, with the intent of determining quantitatively the time-scales of rhyodacite production and accumulation. To help constrain source ages, zircons from the lavas will be analyzed on the CAMECA ion probe at UCLA. Data from the study will then be combined with major and trace element data from another laboratory and published data for more mafic volcanic rocks from the area to understand timescales and differentiation of magmas in subduction zone-related volcanic systems Broader impacts of this work include enabling collaboration between institutions that do not normally work together (University of Iowa, Woods Hole Oceanographic Institute, US Geological Survey, and Michigan State). Societal implications include expanding our knowledge of volcanic eruption timing and caldera formation, which may ultimately help devise strategies for volcanic hazard prediction and mitigation.